Lab Sql agreggation and transformation done

lab aggregation and transformation.sql

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+USE sakila;
+
+SELECT MIN(length) AS min_duration, MAX(length) AS max_duration FROM film;
+
+SELECT CONCAT(FLOOR(AVG(length) / 60), 'h ', FLOOR(AVG(length) % 60), 'm') AS avg_duration_hm
+FROM film;
+
+SELECT DATEDIFF(MAX(rental_date), MIN(rental_date)) AS days_operating
+FROM rental;
+
+SELECT rental_id, rental_date, MONTHNAME(rental_date) AS rental_month, DAYNAME(rental_date) AS rental_weekday
+FROM rental
+ORDER BY rental_date
+LIMIT 20;
+
+SELECT rental_id, rental_date,
+       CASE WHEN DAYOFWEEK(rental_date) IN (1,7) THEN 'weekend' ELSE 'workday' END AS DAY_TYPE
+FROM rental
+ORDER BY rental_date
+LIMIT 20;
+
+SELECT title,
+       COALESCE(CAST(rental_duration AS CHAR), 'Not Available') AS rental_duration
+FROM film
+ORDER BY title ASC;
+
+SELECT CONCAT(first_name, ' ', last_name) AS full_name,
+       SUBSTRING(email, 1, 3) AS email_prefix
+FROM customer
+ORDER BY last_name ASC;
+
+SELECT COUNT(*) AS total_films
+FROM film;
+
+SELECT rating, COUNT(*) AS films_count
+FROM film
+GROUP BY rating;
+
+SELECT rating, COUNT(*) AS films_count
+FROM film
+GROUP BY rating
+ORDER BY films_count DESC;
+
+SELECT rating, ROUND(AVG(length), 2) AS mean_length
+FROM film
+GROUP BY rating
+ORDER BY mean_length DESC;
+
+SELECT rating, ROUND(AVG(length), 2) AS mean_length_over_2h
+FROM film
+GROUP BY rating
+HAVING AVG(length) > 120
+ORDER BY mean_length_over_2h DESC;
+
+SELECT last_name
+FROM actor
+GROUP BY last_name
+HAVING COUNT(*) = 1
+ORDER BY last_name;